Add a pond UVC or pond ultra violet clarifier into the tubing after your pond pump. Place it near to the pumped water's re-entry into the pond to keep the pond water clear summer and winter. Add an ultra violet clarifier (UVC) to your aquarium pump system to reduce the harmful suspended bacteria & organisms & to maintain clear water and healthy fish. Stow it in the cabinet under the aquarium. The unit is rubber sealed to prevent leakage.
Ultra Violet Clarifer